他们觉得，这个人虽然可能有些蒙昧无知，但他决不是一个乐于把自己高贵的天赋用于背信弃义的人。

They felt it might be a being partially benighted in the vale of ignorance, but it could not be one who would willingly devote his rich natural gifts to the purposes of wanton treachery.

youdao

吹风笛的人没有料到这背信弃义的一着。

The piper did not expect this treacherous stroke.

youdao

From the French point of view, it's the perfidious Albion already there.

法国人则认为他们是背信弃义的英国佬

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